This invention relates generally to a lifting eyebolt for connection between a workpiece to be lifted and a lifting device, such as a hoist.
A lifting device is normally attached to an eyebolt, which in turn is normally secured to the workpiece or load to be lifted. Because workpieces come in various shapes and usually leave little or no choice as to where a lifting eyebolt can be attached, the eyebolts are regularly subjected to forces at odd angles that often result in large bending and shear stresses. These forces often mandate the use of an oversized eyebolt. However, the use of an oversize bolt may require drilling and tapping a new, larger hole in the workpiece to be lifted.
A lifting eyebolt is most efficient when the force exerted on the eyebolt lies in the plane defined by the eye. This effectiveness deteriorates rapidly as force is applied outside the plane of the eye. Another problem of typical eyebolts is their tendency to bend at the interface to the workpiece. This bending can stress the eyebolt until it shears at the attachment face of the workpiece.
An improvement over existing eyebolts is desirable which allows the eyebolt to be attached securely to a workpiece in a way that ensures that the force from the lifting device can always be made to lie in the plane of the eye. This flexibility will allow the efficient use of properly sized eyebolts and will also result in a prolonged working life for each individual eyebolt. It is also desirable to provide an improved eyebolt assembly that prevents or restricts bending of the eyebolt at the interface to the workpiece.